Solenoid arrangement



March 1968 H. ZIELASKO SOLENOID ARRANGEMENT Filed July 11, 1966 United States Patent fifice 3,372,355 SOLENOID ARRANGEMENT Horst Zielasko, Nord'enham-Einswarden, Germany, assignor to Felten & Guilleaume Carlswerk Alrtiengesellschaft, Cologne-Mulheim, Germany Filed July 11, 1966, Ser. No. 564,282 Claims priority, application Germany, July 20, 1965, F 46,657 10 Claims. (Cl. 335-430) The present invention relates to an improvement in polarized magnetic arrangements applied particularly to sensitive relays.

In the development of polarized magnetic arrangements for operating in conjunction with switching contacts of relays, it has been found that the sensitivity of such relays, can be increased through the application of a magnetic shunt. Heretofore, such arrangements have, however, been constructed of numerous parts which were connected through press-fitted joints, screws and the like. The press-fitting processes by which the parts of the arrangement were joined, have often diminished the desirable properties of these devices by disturbing the carefully annealed state of the magnetic cores. Thus, the deformations of the parts by the press-fitting process, caused alterations in the equilibrium states of the alloys employed in the magnetic materials for the arrangement.

Accordingly, it is an object of the present invention to provide a polarized magnetic arrangement in which the magnetic shunt and the electromagnetic poles are integrally constructed from one strip of material.

Another object of the present invention is to provide a polarized magnetic arrangement, as set forth, in which no parts are either press-fitted or fastened together so tightly that the magnetic properties of the parts are thereby altered.

Yet another object of the present invention is to provide a polarized magnetic arrangement, as set forth, which is applicable to sensitive type of relays by operating on a relatively low amount of current.

Still another object of the present invention is to provide a polarized magnetic arrangement, as set frth,with a permanent magnet forming a magnetic shunt and an air gap associated with such permanent magnet for increasing the sensitivity of the arrangement.

A further object of the present invention is to provide a polarized magnetic arrangement, as set forth, having an armature which aligns itself automatically with the magnetic poles of the arrangement.

A yet further object of the present invention is to provide a polarized magnetic arrangement, as set forth, which is reliable in operation and requires substantially no maintenance.

A still further object of the present invention is to provide a polarized magnetic arrangement, as set forth, which may be manufactured simply and economically.

With the preceding objects in view, the invention includes a supporting frame having a base and a hole through the base, a first and a second post integrally constructed with the base, an electrical coil wound about each post so that the magnetization of the post is changed, when electric current flows through the coil, a rib associated with each of the posts and integral with the frame, a permanent magnetic bridging the ribs and inducing a magnetic field in the posts, the permanent magnet having a hole, an actuator rod passing through the holes in the base and permanent magnet and parallel to the posts, collars associated with the rod and cooperating with the base and the permanent magnet so that the rod is slidably movable within the holes along a predetermined portion of the rod, an armature affixed to one end of the actuator 3,372,355 Patented Mar. 5, 1968 rod and bridging the posts, the armature being spaced from the posts when electric current flows through the coils and being in contact with the posts at all other times, and a spring mounted on the rod and bearing against the armature and the base to retain the armature separated from the posts when electric current flows through the coils and neutralizes the magnetism therein.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing in which:

FIG. 1 is an elecational view of the supporting frame of the polarized magnetic arrangement;

FIG. 2 is a side view of the supporting frame of FIG. 1;

FIG. 3 is a plan view of the supporting frame of FIG. 1;

FIG. 4 is an elevational view showing the assembled construction of the polarized magnetic arrangement; and

FIG. 5 is a plan view of the assembled construction of FIG. 4.

Referring to the drawing, the frame structure of the polarized magnetic arrangement has a base 1 from which are formed the posts or cores 2. These posts 2 may be formed from the base 1 through the application of conventional dies in conjunction with a punch press. When the posts 2 are bent so that they are perpendicular to the base 1, the two slots 3 are generated in the base. These two slots may be employed for securing the base to a chassis or other mounting structure by passing bolts or similar fastening device through the slots 3 and the mounting structure at the underside of the base. Opposite the end of the posts are ribs 4 formed directly from the base. Aside from this, a hole 5 appears at the center of the base. The supporting frame consisting of the base 1, posts 2, slots 3, ribs 4 and hole 5 is an integral structure. All of these elements of the frame may be generated from a single slice of material placed between dies in a punch press.

The posts 2 serve as cores for electromagnets formed as a result of the energizing coils 16 and 17. Associated with these posts is an armature 6. The armature 6 is joined to an actuator rod 7 which is slidably guided by the hole 5 in the base 1. The actuator rod 7 also passes through a bearing type of hole in a permanent magnet 13. The permanent magnet 13 adheres to the ribs 4 of the base 1 which forms a magnetic shunt and serves to increase the sensitivity of the arrangement because, with its presence in the magnetic circuit, a smaller amount of current is required in the coils 16 and 17 to actuate the armature 6. Due to the presence of the permanent magnet 13, the posts 2 are also made magnetic from this source.

The actuator rod 7 resides within a compression spring 18 which maintains an air gap between the armature 6 and the contact surfaces 11 of the cores 2 when the coils 16 and 17 are energized. The spring is designed so that the force exerted by it on the armature is less than the magnetic force of the posts 2, due to the permanent magnet 13. Accordingly, when no current prevails in the coils 16 and 17, the armature is attracted to the posts 2. When on the other hand, electric current circulates through the coils, magnetic fields are induced thereby, which are oppositely directed to the field arising from the permanent magnet. The electromagnetic fields therefore operate to partially neutralize the magnetic effects due to the permanent magnet, and, accordingly, the armature becomes released when current is admitted through the coils.

The compression spring bears with one end against the armature 6 and with the other end against the 'base 1. The width of the air gap between the armature 6 and the contact surfaces 11 is limited by the collar 15 attached to the actuator rod 7. 'It is essential that this air gap be closely controlled because if the air gap is too wide, the solenoid may fail to operate when the coils 16 and 17 are energized. On the other hand, if the air gap is too short, the solenoid actuator may be too sensitive as it may operate on a minute amount of current in the energizing coil. At the same time, the air gap is also dependent upon or determined by the movement required to actuate relay switching contacts that may be associated with the polarized magnetic arrangement or similar such switching or actuating linkage.

The armature 6 rests upon a shoulder of the actuator rod 7, and is secured thereto, by peening over the end 10 of the actuator rod. The surfaces of the armature 6 which contact the cores 2 are polished similar to those of the contact surfaces 11. The peening-over of the actuator rod 7 permits a degree of freedom of motion of the armature 6, so that when the electromagnets are deenergized, the armature 6 is brought completely in contact with the surfaces 11 of the posts 2. It is therefore desirable to include such freedom of motion of the armature 6, since close and complete contact between the contact surfaces of the armature and those of the posts result in optimum operation of the arrangement. At the same time, however, it is desirable to control the amount of freedom of motion of armature 6 in order to prevent wobbling action of the armature. This is accomplished by applying a layer of self-vulcanizing rubber 12 around the peened area. This layer of rubber prevents excessive motion of the armature and, at the samet ime, is not so rigid that it prevents the armature to assume that angle of orientation which brings the contact surfaces of the armature fully in contact with the surfaces 11 of the cores 2. This self-aligning feature of the armature 6 compensates for any tolerances or manufacturing diiferences in the device, and accordingly contributes extensively to the operational life of the polarized magnetic arrangement.

While the invention has been illustrated and described as embodied in electromagnetic actuating apparatus, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention, that others can by applying current knowledge readily adapt it for various applications without omitting features that from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and therefore suchadaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as novel and desired to be secured by Letters Patent is:

1. A polarized magnetic arrangement comprising, in combination, an electromagnetic solenoid unit composed of a base, two spaced pole pieces integral at one end thereof with said base and having free ends and secondary pole portions on said base integral therewith and arranged spaced from each other; a permanent magnet mounted on said electromagnetic solenoid unit in permanent contact with said spaced secondary pole pieces; an armature having portions located in the region of said free ends of said spaced pole pieces; and means mounting said armature movable towards and away from said free ends.

2. A polarized magnetic arrangement according to claim 1, including electric coil means surrounding said pole pieces.

3. A polarized magnetic arrangement according to claim 1, including means permanently tending to move said armature in a direction away from said pole pieces.

4. A polarized magnetic arrangement according to claim 1, wherein said electromagnetic solenoid unit is of soft magnetic material having a 'high permeability and low coercivity.

5. A polarized magnetic arrangement according to claim 3, including spring means associated with said means for tending to permanently move said armature in a direction away from said pole pieces.

6. A polarized magnetic arrangement according to claim 3, wherein said means for permanently tending to move said armature in a direction away from said pole pieces comprises an actuator rod passing through a hole in said base and said permanent magnet; collars associated with said rod and cooperating with said base and said permanent magnet so that said rod is slidably movable within said hole along a predetermined portion of said rod; and a spring mounted on said rod and bearing against said armature and said base so as to tend moving said armature in a direction away from said pole pieces.

7. A polarized magnetic arrangement according to claim 1, wherein said secondary pole portions are ribs projecting from said base, each of said secondary pole portions being associated with one of said pole pieces.

8. A polarized magnetic arrangement according to claim 7, wherein said permanent magnet is in contact with said ribs thereby forming a gap bordered by said permanent magnet, ribs, and base.

9. A polarized magnetic arrangement according to claim 6, wherein said armature is secured to said actuator rod and a flexible substance adhering to said armature and to said rod allows said armature to align itself against said pole pieces when said rod brings said armature in contact therewith.

10. A polarized magnetic arrangement according to claim 9, wherein said flexible substance is self-vulcanizing rubber.

References Cited UNITED STATES PATENTS 2,876,397 3/1959 Wasson 335-230 3,154,728 10/1964 Bordenet 335-236 XR BERNARD A. GILHEANY, Primary Examiner.

GEORGE HARRIS, 1a., Examiner. 

1. A POLARIZED MAGNETIC ARRANGEMENT COMPRISING, IN COMBINATION, AN ELECTROMAGNETIC SOLENOID UNIT COMPOSED OF A BASE, TWO SPACED POLE PIECES INTEGRAL AT ONE END THEREOF WITH SAID BASE AND HAVING FREE ENDS AND SECONDARY POLE PORTIONS ON SAID BASE INTEGRAL THEREWITH AND ARRANGED SPACED FROM EACH OTHER; A PERMANENT MAGNET MOUNTED ON SAID ELECTROMAGNETIC SOLENOID UNIT IN PERMANENT CONTACT WITH SAID SPACED SECONDARY POLE PIECES; AN ARMATURE HAVING PORTIONS LOCATED IN THE REGION OF SAID FREE ENDS OF SAID SPACED POLE PIECES; AND MEANS MOUNTING SAID ARMATURE MOVABLE TOWARDS AND AWAY FROM SAID FREE ENDS. 